Imagine a box.  The box is 10 inches long and 10 inches wide and 10 inches high. A box that size should be large enough to contain 900 regulation playing marbles.

You own the box and you own 899 of the marbles. But imagine I own one of the marbles and I want it back. "Finders keepers," you say, because for the sake of this problem you're some sort of juvenile jackass.  But we strike a deal: if I can reach into the box, blindfolded, fish around a little, and pull out the one marble out of 900 that's mine, then I can have it back.  But if it's not my marble, deal's off, and I only get one try.

The odds of me selecting my marble are 1:900, or 0.00111. Pretty remote odds in anyone's book.

Believe it or not, the reason I bring up this example has to do with the I Ching. A couple weeks ago, I started a little project in which I throw the I Ching once each day, and record the text of the moving, or oracle, line. Today is the 19th day of that project.

There are 64 hexagrams in the I Ching, so I figured it would be a while before I threw any particular hexagram twice.  But in the first 18 days, I somehow managed the seemingly improbable and have already thrown Hexagram 25 (Wu Wang) twice and Hexagram 30 (Li) three times.

Each hexagram has six lines, so there are 384 possible moving lines. The odds of getting any one line are one in 384, but today, Day 19 of my I Ching project, I threw Hexagram 28 (Ta Quo) for a second time. But not only did I throw a third repeat hexagram, today I also got the same moving line, line six, as before.

Again, the odds for any one line are 1:384, but (to nerd out for a minute) the binomial probability of getting the same 1:384 result twice in only 19 tries is 0.00111, or about one in 900. Same as the marble in the little thought experiment above.

So what is the I Ching trying to tell me?  The text of the recurring hexagram reads, in part, "The flood rises above the tallest tree. Amidst a rising tide of human folly... any direction is better than where you now stand." In other words, don't just stand there, do something. Anything.

But my moving line, the sixth, reads "Fording the flooded stream, he disappears beneath the rushing waters and never resurfaces. Misfortune through no fault of his own." Instead of doing nothing, he did something, but what he did turned out to be a fatal move. 

Great.